1. Field of the Invention
The present invention relates to a handheld terminal and in particular to a method and an apparatus for optimizing usage of DSP (digital signal processing) relating to resources of a handheld terminal.
2. Background of the Related Art
In a handheld terminal, a basis value for using a resource is set. As a result, the performance of the terminal is limited by the range of the set basis value. Also, handheld terminals communicate with a network to determine the network's capabilities. When a basis value of the handheld terminal is different from a capability supported by the network, the terminal adjusts the basis value through a negotiation process with the network.
The handheld terminal can, for example, adjust a data transmission speed flexibly according to a protocol by checking whether the network environment is stable or unstable through the negotiation process. However, because the data transmission speed adjusting operation is performed based on the network capability, a method for using resources of the handheld terminal efficiently is not considered.
In general, the network checks a radio channel with reference to a measurement report and allocates the channel a full rate or half rate to manage limited resources efficiently on the basis of the checking result. For example, when a transmission state of the network is unstable, the network allocates the half rate in order to receive more users. More specifically, in the conventional art although data speed is adjusted according to performance of the network, a process for using resources of the handheld terminal efficiently is not considered.
Accordingly, in the conventional art although the handheld terminal supports only the full rate and the network is in the unstable state, in a processing performance of the handheld terminal, only resources fixed to the existing algorithm are used.
However, in the handheld terminal in accordance with the conventional art, in a condition exceeding a processing capability of DSP, throughput of DSP is reduced. And, in the network unstable state, communication quality is lowered, a communication disable state occurs, or in the worst case the handheld terminal may be powered-off. In order to reduce throughput of the DSP, a user has to disable a DSP usage increasing factor or resource manually. However, because it is difficult for the general user to disable the factor or resource, the user may not use an interface appropriately.
In addition, in an application region interlocking with a DTE (data terminal equipment) such as a PC (personal computer) and a PDA (personal digital assistant), although the user knows well detailed contents of specification (V.25 ter, etc.) and sets a specification value using “at command”, an application is impossible because a terminal initialization order (for example; factory reset) by a program therein is received. It is therefore impossible to actually reduce usage of DSP. More specifically, when the network environment is unstable, it is impossible to use resources efficiently because the handheld terminal sets a communication state with the network using fixed basis values for determining a memory, a FIFO (first-in first-out) size, a data frame size, and application of resources (factors) which influence DSP (data compression, DTX (discontinuous transmission usage), etc.,), to name a few.
In addition, in application interlocking with the DTE (PC, PDA, additional terminal, etc.), the user can use an interface such as an ITU (international telecommunication union) V.25 ter, a GSM (Global System for Mobile Communication) 07.07, and a GSM 07.05 as occasion demands. In that case, the user has to have a thorough understanding of the mechanical specification thereof and accurately apply the specification manually. Because it is impossible to apply the specification accurately, system performance is degraded.
In addition, in interlocking with an application program of the DTE, a terminal basis value resetting phenomenon occurs irregularly due to characteristics of the application program. In that case, although the user knows well about contents of the specification, it is impossible for the user to apply the specification smoothly because the specification is automatically varied by the application program.
As described above, in the conventional terminal because it is impossible for the user to use resources efficiently, usage of DSP cannot be reduced. In addition, in a condition exceeding the DSP processing capability, throughput of the DSP is lowered in a network unstable state, communication quality is lowered, a communication impossible state occurs, and in the worst case the handheld terminal is powered-off.